test-driven-development

Enforces red-green-refactor test-driven development workflow for features and bugfixes.

Updated May 8, 2026
One-click install
npx skills add https://github.com/afonsoft/EAF --skill test-driven-development-afonsoft
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: test-driven-development
Source: https://github.com/afonsoft/EAF/tree/main/.claude/skills/test-driven-development
Command: npx skills add https://github.com/afonsoft/EAF --skill test-driven-development-afonsoft

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve? Developers often write production code before tests, producing tests that pass immediately and prove nothing about correctness. This Skill enforces a strict test-first discipline so every feature and bugfix is backed by a test that was watched failing before implementation. ## Core Features & Use Cases - Red-Green-Refactor Enforcement: Guides the full TDD cycle with mandatory verification that tests fail for the right reason before any implementation code is written. - Rationalization Detection: Lists common excuses for skipping TDD (e.g., "too simple to test", "I'll test after") and counters each with concrete reasoning. - Testing Anti-Pattern Reference: Ships a companion reference covering mock-behavior testing, test-only production methods, incomplete mocks, and over-mocking. - Use Case: When fixing a bug where empty emails are accepted, write a failing test asserting the rejection error, watch it fail, implement minimal validation, then refactor while keeping tests green. ## Quick Start Ask the AI to implement a new feature or bugfix using strict test-driven development, writing the failing test first before any production code.

Frequently Asked Questions about test-driven-development

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I practice test-driven development on a new feature?▼

Write one minimal failing test describing the desired behavior, run it to confirm it fails for the right reason, then write the simplest code that passes. Refactor only while tests stay green, then repeat the cycle for the next behavior.

How do I write a failing test for a bug fix?▼

Write a test that reproduces the bug by asserting the correct expected behavior, then run it to watch it fail. Implement the minimal fix until the test passes, which both proves the fix and prevents regression.

Why should tests be written before implementation code?▼

Tests written after code pass immediately, which proves nothing about whether they test the right behavior. Watching a test fail first confirms it actually exercises the missing feature rather than a typo or existing behavior.

When is it acceptable to skip test-driven development?▼

Possible exceptions include throwaway prototypes, generated code, and configuration files, but only with explicit approval from your human partner. Exploration is allowed if the exploratory code is discarded and rewritten test-first.

What are common testing anti-patterns with mocks?▼

Common anti-patterns include asserting on mock elements instead of real behavior, adding test-only methods to production classes, mocking without understanding side effects, and creating incomplete mocks missing fields downstream code uses.